Synthesis, characterization and crystal structure determination of aluminum hydride complexes of N, N′- Di(isopropyl)ethylenediamine ligand

How to Decarbonize N‐Heterocyclic Carbenes (NHCs): The simple Alane Adducts (NHC) ⋅ AlR3 (R=H, Me, Et)

“…The results of the XRD revealed that the compound formed is the dimer cis-[AlH{μ-N(Dipp)CH 2 CH 2 N(Dipp)}] 2 4_dimer (Figure 4). The bond lengths of terminal Al1À N1 and Al2À N4 (1.8187(13) and 1.8202( 14) Å) are significantly shorter than those observed for the bridging AlÀ μÀ N bonds which lie in the range of 1.9793(13)-2.0128(13) Å. Dimeric structures for amide supported aluminum compounds via bridging amide ligands are well-known in the literature as highlighted by closely related [AlH{μ-N(tBu)CH 2 CH 2 N(tBu)}] 2 , synthesized by Raston et al, [25] [AlH{μ-N( i Pr)CH 2 CH 2 N(iPr)}] 2 , reported by Jana et al, [26] or by the molecular structures of [(Me 2 N)(H)Al(μ-NMe 2 )] 2 and [(H 2 Al{μ-N(CH 2 ) 5 })]. [27] It should be noted here that compound 4_dimer was already synthesized by Crimmin et al via the reaction of the corresponding N,N'-bis(di-isopropylphenyl)ethylenediamine with (NMe 3 ) • AlH 3 to yield the monomeric, amine-ligated compound 4 • (NMe 3 ), and Roesky et al also reported closely related compounds previously.…”

Zur Dekarbonisierung N‐Heterocyclischer Carbene (NHCs): Die einfachen Alan‐Addukte (NHC) ⋅ AlR3 (R=H, Me, Et)

“…[10] Da die meisten bekannten RER von NHCs mit Hydriden der Hauptgruppen-Elemente bei erhöhten Temperaturen stattfinden, haben wir auch die Reaktion von äquimolaren Mengen an (NMe Mengen. [14] Interessanterweise lässt sich die Stammverbindung (SIDipp) • AlH 3 2 bereits bei Raumtemperatur durch Zugabe der sterisch weniger anspruchsvollen NHCs IMe Me , IiPr Me , [25] und [AlH{μ-N-( i Pr)CH 2 CH 2 N( i Pr)}] 2 , berichtet von Jana et al, [26] oder aber die Molekülstrukturen von [(Me 2 N)(H)Al(μ-NMe 2 )] 2 und [(H 2 Al{μ-N(CH 2 ) 5 })] belegen. [27] An dieser Stelle sei angemerkt, dass Verbindung 4_dimer bereits von Crimmin et al durch die Reaktion des entsprechenden N,N'-Bis(di-isopropylphenyl)-ethylenediamins mit (NMe 3 ) • AlH 3 synthetisiert wurde, woraus die monomere, Amin-stabilisierte Verbindung 4 • (NMe 3 ) hervorgeht.…”